For example, a vehicle battery unit described in Patent Document 1 is known as a vehicle battery unit for use in an electric vehicle. In Patent Document 1, a battery unit is disposed underneath a floor panel of a vehicle. An air intake port is provided at a front of a battery case having a battery accommodation space where a battery is accommodated, and cooling air is taken into from the air intake port and is discharged from an air discharge port which is provided at a rear of the battery case, whereby a battery is cooled directly by the cooling air to restrain the battery from being heated.
Additionally, Patent Document 1 discloses a configuration in which a water absorbing member is disposed above a location where the formation of dew should be avoided in consideration of the influence of dew formed within the battery case to thereby prevent the occurrence of a drawback associated with the formation of dew.